Culinarily, what we think of a scallop is the scallop’s adductor muscle (which is far more well-developed in scallops than it is in e.g. an oyster, allowing them to swim). There’s also scallop roe, both male and female, which I won’t get into here.

Lastly, note that a scallop should not be confused with a shallot, which is a small sort of oniony thing, or a scallion, also known as green onion, which is an oniony-tasting plant.